Ultraviolet light sources, such as sunlight, are particularly detrimental to many articles of manufacture whether such articles be made of natural or man-made materials. For example, sunlight is particularly detrimental to window coverings and furnishings within a residential dwelling as well as commercial buildings of all types.
Accordingly, it is desirable to minimize the damage to the structure and appearance of certain articles, such as window coverings, carpeting and furnishings within a dwelling or other type of human occupied building, while at the same time allowing sufficient light to the room or rooms of the building to satisfy human needs as well as aesthetic qualities or characteristics of the room. For example, window coverings known as sheers are hung in many windows in addition to completely opaque window coverings, such as draperies and the like, to allow light to enter the room and to also permit humans occupying the room to see through the fabric of the sheers to the outside world. However, heretofore, fabrics used for and the light transmitting characteristics of known types of sheers have been unsuitable to prevent damage from ultraviolet radiation or light to the sheers themselves, as well as to opaque window coverings and the furnishings within the room at which the window coverings are hung.
Taking into account the vast number of residential dwellings, commercial office buildings, hotels and other buildings which are windowed and suffer from damage due to ultraviolet light, there has been a substantial need to provide improved window coverings which will reduce such damage while at the same time providing for admission of substantial natural light into the interior of the dwelling or building and to permit human occupants to see through the window coverings to the outside world.